The downlink for very low power wireless local area network (WLAN) devices is problematic. The device needs to wake up according to some internal schedule and determine if the access point (AP) has data for it. In devices that are operable in wireless networks that conform to the Institute for Electronic and Electrical Engineers (IEEE) 802.11 standard, that means either checking for a TIM bit in the beacon, or sending a trigger or poll frame to the AP.
If the device is intended for very low power operation and only very infrequently receives data (e.g. control parameters to a temperature sensor), this waking up process usually discovers there is no data and therefore may waste a great amount of power.
Thus, a critical need is prevalent for techniques for wakeup signaling for a very low power WLAN device.
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